1 Introduction Over the past decade or so, the internet/web has dramatically transformed our societies and changed our lives in many different ways, from simple electronic news publishing to many forms(e. g, business-to-cons peer-to-peer, etc.), all of which can be done anywhere, anytime, and by anyone One of the advances in this net/web arena is distributed object computing in the form of internet appliances. This is where a client device(e.g, a PC, PDA, cellular phone)can communicate with, say, a net-aware refrigerator, which in turn can make a maintenance call to a repair store and order groceries from an online grocer.(IBM had a TV commercial that describes this very scenario to showcase the future of internet appliance computing)With the advent of mobile technologies [1] and location-based services [2] the ability to use a device such as a PDa to conduct business transactions(e.g, pay for a soda in a vending machine(another TV commercial on the future of computing), locate the nearest Starbuck coffee shop, etc. )is especially intriguing In the above example, all these devices are examples of internet appliances, and they communicate to each other via some common protocol. a protocol that has received a lot of attention is the architecture by Sun Microsystems known as JiniM[3-7]. Jini, created by Bill Joy, who is often known as the 'Edison of Silicon Valley,, leverages the unique distributed computing characteristics of Java technology, specifically its ability to move both code and data from machine to machine, to create a ubiquitous network One of the goals of Jini technology is to make adding an electronic device to a network as easy as plugging in the base unit of a new cordless phone- in other words, us network'or network plug and play. Another goal of Jini is to make distributed computing a near-term reality, i. e, allow computing capabilities to be shared among many diverse machines across a common network. Jini technology lets users easily access the needed power and features of any appropriate device on the network by creating federations'or communities of shared data, storage, and computing power. From the perspective of Jini, there is no real distinction between hardware such as a printer, scanner, or dishwasher and software such as Ms Word- everything is considered a service. That is why Jini is considered as 'service-oriented architecture'(SOA)[8, 9 a Jini-enabled service, when started, can spontaneously connect to a network and broadcast its presence and what it can do. a client can search the network, find the service, and use it without configuration. There is no need to set up an IP address, gateway or router,i.e, true plug and play that is'administration free. For instance, when plugged into a network, a Jini-enabled printer can broadcast its presence and capability. Then, a Jini-enabled digital camera can find the printer and send a picture to be printed With the popularity of wireless devices all around the world, one can imagine that a technology that supports spontaneous computing such as Jini will play a major role in today's IT evolution. This is because wireless devices, such as mobile phones, PDAs, and pagers, are ideal for joining dynamic, spontaneous networks. Indeed, because of the promises of Jini, many major vendors have already announced support for the technology. These companies are actively architecting Jini technology into a new breed of consumer products and services. It has broadened beyond the device space to encompass service delivery to and from enterprises as well. Examples of use of the technology by well-known organisations include Cisco's scalable communication framework, Ford's and Daimler Chryslers I cruiser telematics systems, and the Us200 B. Lim and H. Zheng 1 Introduction Over the past decade or so, the internet/web has dramatically transformed our societies and changed our lives in many different ways, from simple electronic news publishing to e-commerce in many different forms (e.g., business-to-consumer, business-to-business, peer-to-peer, etc.), all of which can be done anywhere, anytime, and by anyone. One of the advances in this net/web arena is distributed object computing in the form of internet appliances. This is where a client device (e.g., a PC, PDA, cellular phone) can communicate with, say, a net-aware refrigerator, which in turn can make a maintenance call to a repair store and order groceries from an online grocer. (IBM had a TV commercial that describes this very scenario to showcase the future of internet appliance computing.) With the advent of mobile technologies [1] and location-based services [2], the ability to use a device such as a PDA to conduct business transactions (e.g., pay for a soda in a vending machine (another TV commercial on the future of computing), locate the nearest Starbuck coffee shop, etc.) is especially intriguing. In the above example, all these devices are examples of internet appliances, and they communicate to each other via some common protocol. A protocol that has received a lot of attention is the architecture by Sun Microsystems known as Jini [3–7]. Jini, created by Bill Joy, who is often known as the ‘Edison of Silicon Valley’, leverages the unique distributed computing characteristics of Java technology, specifically its ability to move both code and data from machine to machine, to create a ubiquitous network. One of the goals of Jini technology is to make adding an electronic device to a network as easy as plugging in the base unit of a new cordless phone – in other words, ‘spontaneous network’ or ‘network plug and play’. Another goal of Jini is to make distributed computing a near-term reality, i.e., allow computing capabilities to be shared among many diverse machines across a common network. Jini technology lets users easily access the needed power and features of any appropriate device on the network by creating ‘federations’ or communities of shared data, storage, and computing power. From the perspective of Jini, there is no real distinction between hardware such as a printer, scanner, or dishwasher and software such as MS Word – everything is considered a service. That is why Jini is considered as ‘service-oriented architecture’ (SOA) [8,9]. A Jini-enabled service, when started, can spontaneously connect to a network and broadcast its presence and what it can do. A client can search the network, find the service, and use it without configuration. There is no need to set up an IP address, gateway, or router, i.e., true plug and play that is ‘administration free’. For instance, when plugged into a network, a Jini-enabled printer can broadcast its presence and capability. Then, a Jini-enabled digital camera can find the printer and send a picture to be printed. With the popularity of wireless devices all around the world, one can imagine that a technology that supports spontaneous computing such as Jini will play a major role in today’s IT evolution. This is because wireless devices, such as mobile phones, PDAs, and pagers, are ideal for joining dynamic, spontaneous networks. Indeed, because of the promises of Jini, many major vendors have already announced support for the technology. These companies are actively architecting Jini technology into a new breed of consumer products and services. It has broadened beyond the device space to encompass service delivery to and from enterprises as well. Examples of use of the technology by well-known organisations include Cisco’s scalable communication framework, Ford’s and DaimlerChrysler’s IT cruiser telematics systems, and the US